Sheriff Walt Longmire, his long-time friend Henry Standing Bear, and his undersheriff Victoria Moretti are returning from a fishing trip in the Bighorn Mountains when Walt receives a distress call from Crazy Woman Canyon. Forest service ranger Chuck Coon is in trouble. Walt, the Bear, and Vic arrive to find Coon and a young woman up a tree, so to speak. The unlikley duo are fending off three very real bears from the top of a Porta Potty and tell a mystifying story of another dangerous creature inside the "convenience." When Walt, Henry, and Vic face the creature what they find may be a Messenger from the Camp of the Dead, with a very personal tie to Walt himself.